1. Field of the Invention
This invention relates to an internal shoe drum brake, primarily for a motor vehicle, and having a pair of brake shoes mounted on a backplate and separable by an actuator into braking engagement with a rotatable brake drum against the action of resilient return means in the form of a generally C-shaped element of which an intermediate portion is retained on the backplate by retention means fast with the latter, and of which portions spaced longitudinally from the intermediate portion cooperate with the shoes in a manner such as to produce an inward shoe return force.
2. Description of Related Art
It has been proposed to retain the spring in a brake of this kind by providing one or more pairs of integral lugs in the backplate which define slots arranged in a plane generally perpendicular to the backplate so as to retain the spring in a direction generally parallel to the backplate. In addition, the spring is usually retained in a direction perpendicular to the backplate by way of a separate retaining device secured to the backplate. This slotted arrangement tends to create stress points in the backplate which can give rise to cracking thereof in use and one object of the invention is to provide a spring retention means which is less prone to this problem.